First step towards moving AudioDevice from content/ to media/audio.

content/renderer/media/audio_input_device.h

Index: content/renderer/media/audio_input_device.h
diff --git a/content/renderer/media/audio_input_device.h b/content/renderer/media/audio_input_device.h
index 8ef72b7e277704866cce16215f96b760ab671ad3..7a06a9aa8300c70e1b88ad6e4ee14fac87f7c26d 100644
--- a/content/renderer/media/audio_input_device.h
+++ b/content/renderer/media/audio_input_device.h
@@ -61,7 +61,7 @@
 // Implementation notes:
 //
 // - Start() is asynchronous/non-blocking.
-// - Stop() is synchronous/blocking.
+// - Stop() is asynchronous/non-blocking.
 // - SetDevice() is asynchronous/non-blocking.
 // - The user must call Stop() before deleting the class instance.
 
@@ -87,7 +87,7 @@
 // OnCaptureStopped etc.) and ensure that we can deliver these notifications
 // to any clients using this class.
 class CONTENT_EXPORT AudioInputDevice
-    : public AudioInputMessageFilter::Delegate,
+    : NON_EXPORTED_BASE(public media::AudioInputIPCDelegate),
       NON_EXPORTED_BASE(public ScopedLoopObserver),
       public base::RefCountedThreadSafe<AudioInputDevice> {
  public:
@@ -117,9 +117,12 @@ class CONTENT_EXPORT AudioInputDevice
   };
 
   // Methods called on main render thread -------------------------------------
-  AudioInputDevice(const media::AudioParameters& params,
-                   CaptureCallback* callback,
-                   CaptureEventHandler* event_handler);
+  AudioInputDevice(media::AudioInputIPC* ipc,
+                   const scoped_refptr<base::MessageLoopProxy>& io_loop);
+
+  void Initialize(const media::AudioParameters& params,
+                  CaptureCallback* callback,
+                  CaptureEventHandler* event_handler);
 
   // Specify the |session_id| to query which device to use. This method is
   // asynchronous/non-blocking.
@@ -142,13 +145,9 @@ class CONTENT_EXPORT AudioInputDevice
   // Returns |true| on success.
   bool GetVolume(double* volume);
 
-  double sample_rate() const {
-    return audio_parameters_.sample_rate();
-  }
+  double sample_rate() const { return audio_parameters_.sample_rate(); }
 
-  int buffer_size() const {
-    return audio_parameters_.frames_per_buffer();
-  }
+  int buffer_size() const { return audio_parameters_.frames_per_buffer(); }
 
   // Sets the Automatic Gain Control state to on or off.
   // This method must be called before Start(). It will not have any effect
@@ -156,13 +155,15 @@ class CONTENT_EXPORT AudioInputDevice
   void SetAutomaticGainControl(bool enabled);
 
   // Methods called on IO thread ----------------------------------------------
-  // AudioInputMessageFilter::Delegate impl., called by AudioInputMessageFilter.
+  // media::AudioInputIPCDelegate implementation.
   virtual void OnStreamCreated(base::SharedMemoryHandle handle,
                                base::SyncSocket::Handle socket_handle,
-                               uint32 length) OVERRIDE;
+                               int length) OVERRIDE;
   virtual void OnVolume(double volume) OVERRIDE;
-  virtual void OnStateChanged(AudioStreamState state) OVERRIDE;
+  virtual void OnStateChanged(
+      media::AudioInputIPCDelegate::State state) OVERRIDE;
   virtual void OnDeviceReady(const std::string& device_id) OVERRIDE;
+  virtual void OnIPCClosed() OVERRIDE;
 
  protected:
   virtual ~AudioInputDevice();
@@ -181,8 +182,6 @@ class CONTENT_EXPORT AudioInputDevice
   void SetVolumeOnIOThread(double volume);
   void SetAutomaticGainControlOnIOThread(bool enabled);
 
-  void Send(IPC::Message* message);
-
   // MessageLoop::DestructionObserver implementation for the IO loop.
   // If the IO loop dies before we do, we shut down the audio thread from here.
   virtual void WillDestroyCurrentMessageLoop() OVERRIDE;
@@ -193,14 +192,10 @@ class CONTENT_EXPORT AudioInputDevice
   CaptureCallback* callback_;
   CaptureEventHandler* event_handler_;
 
-  // The current volume scaling [0.0, 1.0] of the audio stream.
-  double volume_;
-
-  // Cached audio input message filter (lives on the main render thread).
-  scoped_refptr<AudioInputMessageFilter> filter_;
+  media::AudioInputIPC* ipc_;
 
   // Our stream ID on the message filter. Only modified on the IO thread.
-  int32 stream_id_;
+  int stream_id_;
 
   // The media session ID used to identify which input device to be started.
   // Only modified on the IO thread.